This is a request for a bioengineering research grant to establish micro CT methods for imaging mouse lungs in a repeatable manner such that image data is suitable for quantitating regional lung structure including parenchymal density. Methods for identifying the lung, lung lobes, airways and alveolar structure will be established. We will use these methods to then establish an atlas database/knowledgebase for C57BI/6J mice and another database for A/J mice due to the anatomical variability across these strains. Upon completion of this project we will have produced normative anatomical reference databases for the C57BI/6J and A/J mice stains consisting of image data from 10 mice each and geometrical measurements from a total of 100 mice each. Image data from all 100 mice will be stored off line, but we limit the image data to be held on line to 10 from each strain out of consideration for practical limitations to on-line "live" data storage considerations. Each mouse will have at least 3 volumetric image data sets, segmentation results, meshed datasets for use in CFD and other modeling studies, texture results, etc. the knowledge gained in this project will allow us to provide recommendations for constructing future databases for other strains and scenarios. Furthermore, we emphasize that we will not only make the atlas available publicly, we will welcome other groups to contribute measurements and categorizations associated with the data set which we do not provide (or which improve upon or differ in some way from those measures which we provide). The atlas databases will be constructed by building models from high resolution MicroCT scans and 3D pathological images of in situ lungs from freshly dead mice. Image data used to construct each atlas database will consist of MicroCT images at 3 lung volumes (5, 10 and 25 cmH2O) and pathological images at one lung volume (25 cmH2O). Through a collaboration with Drs Ochs and Weibel, we will also establish the correlations between micro-CT and microscopy-based methods. Microscopy will be used to also provide supplemental data to the mouse atlas. Methods will be developed to follow living mice via Micro CT to allow for the tracking of pathologic processes to aid in the decision as to appropriate time points for more detailed post mortem, in situ analyses through comparisons between the individual and the normative atlas.